Superior Long-term Survival for Simultaneous Pancreas-Kidney Transplantation as Renal Replacement Therapy: 30-Year Follow-up of a Nationwide Cohort.

OBJECTIVE: In patients with type 1 diabetes and end-stage renal disease, it is controversial whether a simultaneous pancreas-kidney (SPK) transplantation improves survival compared with kidney transplantation alone. We compared long-term survival in SPK and living- or deceased-donor kidney transplant recipients. RESEARCH DESIGN AND METHODS: We included all 2,796 patients with type 1 diabetes in the Netherlands who started renal replacement therapy between 1986 and 2016. We used multivariable Cox regression analyses adjusted for recipient age and sex, dialysis modality and vintage, transplantation era, and donor age to compare all-cause mortality between deceased- or living-donor kidney and SPK transplant recipients. Separately, we analyzed mortality between regions where SPK transplant was the preferred intervention (80% SPK) versus regions where a kidney transplant alone was favored (30% SPK). RESULTS: Of 996 transplanted patients, 42%, 16%, and 42% received a deceased- or living-donor kidney or SPK transplant, respectively. Mean (SD) age at transplantation was 50 (11), 48 (11), and 42 (8) years, respectively. Median (95% CI) survival time was 7.3 (6.2; 8.3), 10.5 (7.2; 13.7), and 16.5 (15.1; 17.9) years, respectively. SPK recipients with a functioning pancreas graft at 1 year (91%) had the highest survival (median 17.4 years). Compared with deceased-donor kidney transplant recipients, adjusted hazard ratios (95% CI) for 10- and 20-year all-cause mortality were 0.79 (0.49; 1.29) and 0.98 (0.69; 1.39) for living-donor kidney and 0.67 (0.46; 0.98) and 0.79 (0.60; 1.05) for SPK recipients, respectively. A treatment strategy favoring SPK over kidney transplantation alone showed 10- and 20-year mortality hazard ratios of 0.56 (0.40; 0.78) and 0.69 (0.52; 0.90), respectively. CONCLUSIONS: Compared with living- or deceased-donor kidney transplantation, SPK transplant was associated with improved patient survival, especially in recipients with a long-term functioning pancreatic graft, and resulted in an almost twofold lower 10-year mortality rate.